Slim-type vapor chamber and capillary structure thereof

ABSTRACT

A slim-type vapor chamber and a capillary structure thereof are provided, including an upper board and a lower board. The upper and lower boards respectively include a metal plate. Trenches are formed on one side surface of the metal plate. The upper board and the lower board overlap each other to make the corresponding side surfaces of the two metal plates contact each other. The trenches of the two metal plates are correspondingly disposed to form passages. The trenches of one of the metal plates are staggered from the trenches of the other metal plate by an offset distance to form staggered passages. Therefore, the capillary force during reverse flow of a working fluid is enhanced, the contact area between the vapor and the passage is increased, and the heat transfer efficiency of the vapor chamber is improved.

BACKGROUND

1. Technical Field

The present invention relates to a vapor chamber and, in particular, to a slim-type vapor chamber and a capillary structure thereof.

2. Related Art

A vapor chamber is a heat dissipation device that can rapidly spread heat from a small source to a plate of large area. The vapor chamber has characteristics such as great heat transfer efficiency, reduced weight, simple structure, and versatility, and it can transfer a great amount of heat without electric power consumption, so the vapor chamber is extensively used in the market of high performance heat dissipation components, for example, it is applied to servers, communication components, high-quality graphics cards, and high-efficiency LED heat dissipation components.

A conventional vapor chamber is a vacuum chamber consisting of an upper metal plate and a lower metal plate welded together. An inner wall of the vapor chamber includes capillary structures and a working fluid. Furthermore, the heat transfer capability of the vapor chamber is mainly decided by the material and the disposition layout of the capillary structures. The disposition layout of the capillary structure affects a reverse-flow speed of the liquid working fluid. When the reverse-flow speed of the working fluid is slow, and the conveyance time of the liquid working fluid is long, a dry-out condition of the vapor chamber easily occurs.

On the other hand, along with the development of light and thin electronic apparatuses, there have been increasing demands for vapor chamber made as thin and light as possible. Accordingly, the inventor of the present invention is motivated to improve a capillary structure of a slim-type vapor chamber, so as to provide the slim-type vapor chamber with excellent heat transfer capability.

In view of the foregoing, the inventor made various studies to improve the above-mentioned problems to overcome the above-mentioned drawback, on the basis of which the disclosed example is accomplished.

BRIEF SUMMARY

It is an objective of the present invention to provide a slim-type vapor chamber and a capillary structure thereof, wherein a liquid reverse-flow trench of one metal plate is staggered from a liquid reverse-flow trench of the other metal plate by an offset distance to form a liquid reverse-flow passage which is not flush at the left and right edges, thereby enhancing the capillary force during reverse flow of a working fluid and increasing the heat transfer efficiency of the vapor chamber.

Accordingly, the present invention provides a capillary structure of a slim-type vapor chamber, which comprises an upper board and a lower board. The upper board includes a first metal plate, and a plurality of first trenches are formed on one side surface of the first metal plate. The lower board includes a second metal plate, and a plurality of second trenches are formed on one side surface of the second metal plate. The upper board and the lower board overlap each other to make the two corresponding side surfaces of the first metal plate and the second metal plate contact each other. The second trenches are staggered from the first trenches by an offset distance to form a plurality of staggered passages.

Accordingly, the present invention provides a slim-type vapor chamber including a capillary structure thereof and a working fluid. The working fluid is filled between the upper board and the lower board.

Compared to conventional techniques, the slim-type vapor chamber and the capillary structure thereof according to the present invention is featured in that, the trenches of the two metal plates are disposed in a staggered manner to form staggered liquid reverse-flow passages or staggered vapor passages. When the working fluid is in each liquid reverse-flow passage, the capillary force during reverse flow of the working fluid has a larger contact surface with the liquid reverse-flow passage. Therefore, in the present invention, the liquid reverse-flow trenches are so staggeredly disposed that the working fluid has a larger contact area in each liquid reverse-flow passage, thereby enhancing the reverse-flow strength of the working fluid. Furthermore, when the first liquid reverse-flow trenches contact the second liquid reverse-flow trenches, in a staggered manner with an offset distance, to form right-angle areas or acute-angle areas, such areas enhance the capillary force of the working fluid in the reverse-flow passage, thereby increasing the capillary force during reverse flow. Furthermore, when the second vapor trenches and the first vapor trenches are disposed in a staggered manner to form a plurality of staggered vapor passages, the staggered vapor passages can increase the heat contact area between the vapor and the passage, thereby enhancing the heat transfer rate to improve the heat dissipation efficiency. As a result, dry-out of the vapor chamber is avoided, and the heat transfer efficiency of the vapor chamber is enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:

FIG. 1 is a perspective appearance view of a metal plate of a slim-type vapor chamber according to the present invention.

FIG. 2 is a partially enlarged view of the metal plate of the slim-type vapor chamber according to the present invention.

FIG. 3 is a schematic view illustrating a combination relationship of the slim-type vapor chamber according to the present invention.

FIG. 4 is a schematic view illustrating a combination relationship of a portion of the slim-type vapor chamber according to the present invention.

FIG. 5 is a cross-sectional view illustrating a combined state of the slim-type vapor chamber according to the present invention.

FIG. 6 is a schematic view illustrating staggered passages of the slim-type vapor chamber according to a first embodiment of the present invention.

FIG. 7 is a schematic view illustrating the staggered passages of the slim-type vapor chamber according to a second embodiment of the present invention.

FIG. 8 is a schematic view illustrating the staggered passages of the slim-type vapor chamber according to a third embodiment of the present invention.

DETAILED DESCRIPTION

In the following, detailed descriptions along with accompanied drawings are given to better explain the features and technical contents of the example embodiment. However, the following descriptions and the accompanied drawings are for reference and illustration only, and are not intended to limit the scope of the example embodiment.

Please refer to FIGS. 1 to 3 which are a perspective appearance view and a partially enlarged view of a metal plate of a slim-type vapor chamber and a schematic view illustrating the combination relationship of the slim-type vapor chamber according to the present invention. The present invention provides a capillary structure of a slim-type vapor chamber, which comprises an upper board 10 and a lower board 20. The upper board 10 and the lower board 20 overlap each other and are secured together in such a manner that a closed space is formed between them. Furthermore, the present invention also provides a slim-type vapor chamber 1. The slim-type vapor chamber 1 further includes a working fluid. The working fluid is filled between the upper board 10 and the lower board 20. Preferably, the thickness of the slim-type vapor chamber 1 is below 1 mm. In other words, the upper board 10 and the lower board 20 respectively have a thickness below 0.5 mm.

Please refer to FIGS. 1 and 2, in which the upper board 10 is illustrated as an example to describe the disposition layout of the capillary structure. The disposition layout of the capillary structure of the lower board 20 is substantially the same as that of the upper board 10; however, the difference is the relative position relationship between the capillary structure of the upper board 10 and the capillary structure of lower board 20, which will be described further later.

The upper board 10 includes a first metal plate 11. A plurality of first trenches 110 are formed on one side surface of the first metal plate 11. The first trenches 110 include a plurality of first vapor trenches 12 and a plurality of first liquid reverse-flow trenches 13. According to the present embodiment, the first trenches 110 extend from one side to the opposite side of the first metal plate 11; however, in the practical practice, the present invention is not limited thereto.

Referring to FIG. 3, similarly, the lower board 20 includes a second metal plate 21. A plurality of second trenches 210 are formed on one side surface of the second metal plate 21. The second trenches 210 include a plurality of second vapor trenches 22 and a plurality of second liquid reverse-flow trenches 23. According to the present embodiment, the second trenches 210 extend from one side to the opposite side of the second metal plate 21. Furthermore, the first vapor trenches 12, the first liquid reverse-flow trenches 13, the second vapor trenches 22, and the second liquid reverse-flow trenches 23 are arranged in parallel relation; however, in the practical practice, the present invention is not limited thereto, and the disposition layout can be in radial or other relationship.

It is preferable that the first vapor trenches 12 and the first liquid reverse-flow trenches 13 are formed on the first metal plate 11 by an electroforming method or an etching method. Furthermore, the second vapor trenches 22 and the second liquid reverse-flow trenches 23 are formed on the second metal plate 21 by an electroforming method or an etching method.

According to the present embodiment, the first metal plate 11 is further formed with a plurality of first supplementary liquid reverse-flow trenches 14 at one side of the first liquid reverse-flow trenches 13. Moreover, the second metal plate 21 is further formed with a plurality of second supplementary liquid reverse-flow trenches 24 corresponding to the second liquid reverse-flow trenches 23. The second supplementary liquid reverse-flow trenches 24 extend from one side to the other opposite side of the second metal plate 21. According to the present embodiment, the first supplementary liquid reverse-flow trenches 14 extend from one side to the other opposite side of the second metal plate 11. Furthermore, the first supplementary liquid reverse-flow trenches 14 and the second supplementary liquid reverse-flow trenches 24 are arranged in a parallel manner; however, in the practical practice, the present invention is not limited thereto, and the disposition layout can be in radial or other relationship.

Moreover, the first metal plate 11 is formed with a plurality of first liquid transverse reverse-flow trenches 15 perpendicular to the first vapor trenches 12. The second metal plate 21 is formed with a plurality of second liquid transverse reverse-flow trenches (not illustrated) perpendicular to the second vapor trenches 22. The first liquid transverse reverse-flow trenches 15 and the second liquid transverse reverse-flow trenches are correspondingly disposed to form a plurality of liquid transverse reverse-flow passages (not illustrated).

According to one embodiment of the present invention, a distal end of the first vapor trenches 12 of the first metal plate 11 includes a plurality of first distal-end liquid reverse-flow trenches 16. Similarly, a distal end of the second vapor trenches 22 of the second metal plate 21 includes a plurality of second distal-end liquid reverse-flow trenches (not illustrated). The first distal-end liquid reverse-flow trenches 16 and the second distal-end liquid reverse-flow trenches are correspondingly disposed to form a plurality of distal-end liquid reverse-flow passages (not illustrated). It should be noted that, the disposition of the first liquid transverse reverse-flow trenches 15 and the second liquid transverse reverse-flow trenches and the disposition of the first distal-end liquid reverse-flow trenches 16 and the second distal-end liquid reverse-flow trenches can provide more reverse-flow space for the working fluid, thereby increasing the reverse-flow rate of the working fluid.

Please refer to FIG. 4 which is a schematic view illustrating a combination relationship of a portion of the slim-type vapor chamber according to the present invention, and please refer to FIG. 5 which is a cross-sectional view illustrating a combined state of the slim-type vapor chamber according to the present invention. According to the present embodiment, the upper board 10 and the lower board 20 overlap each other to make the two corresponding side surfaces of the first metal plate 11 and the second metal plate 21 contact each other.

In detail, the first metal plate 11 and the second metal plate 21 contact each other, and the first vapor trenches 12 and the second vapor trenches 22 are disposed correspondingly, so as to form a plurality of vapor passages 102 upon contact. Furthermore, the first liquid reverse-flow trenches 13 and the second liquid reverse-flow trenches 23 are correspondingly disposed to form a plurality of liquid reverse-flow passages 103. It should be noted that, the second trenches 210 of the second metal plate 21 are staggered from the first trenches 110 of the first metal plate 11 by an offset distance S to form a plurality of staggered passages 100′, which will be described in detail later.

Please refer to FIGS. 6 to 8 which illustrate the staggered passages of the slim-type vapor chamber of the present invention according to three kinds of embodiments respectively. Referring to FIG. 6, the second liquid reverse-flow trenches 23 are staggered from the first liquid reverse-flow trenches 13 by an offset distance S, and the second liquid reverse-flow trenches 23 contact the first liquid reverse-flow trenches 13 to form a plurality of staggered liquid reverse-flow passages 103′. Furthermore, the first supplementary liquid reverse-flow trenches 14 and the second supplementary liquid reverse-flow trenches 24 are correspondingly disposed to form a plurality of supplementary liquid reverse-flow passages 104.

When the working fluid is in each of the staggered liquid reverse-flow passages 103′, the heat transfer efficiency increases if the working fluid has a larger contact area with the staggered liquid reverse-flow passages 103′. By means of the offset distance S between the first liquid reverse-flow trenches 13 and the second liquid reverse-flow trenches 23, the working fluid in each of the staggered liquid reverse-flow passages 103′ has a larger contact area. It should be noted that, when the first liquid reverse-flow trenches 13 contact the second liquid reverse-flow trenches 23, in a staggered manner with an offset distance S, to form two right-angle/acute-angle areas A, the two areas A enhance the capillary force effect of the working fluid in the staggered liquid reverse-flow passages 103′, thereby improving the reverse-flow strength.

For example, in the case that the first liquid reverse-flow trenches 13 and the second liquid reverse-flow trenches 23 respectively have a same width of W, it is preferable that the offset distance S between the first liquid reverse-flow trenches 13 and the second liquid reverse-flow trenches 23 is below ¾W. The offset distance is ¼W or ½W for example. Accordingly, the working fluid in each of the staggered liquid reverse-flow passages 103′ has a larger contact area, so as to enhance the reverse-flow strength of the working fluid.

Referring to FIG. 7 showing an embodiment different from FIG. 6, the difference between the present embodiment and FIG. 6 lies in that the second vapor trenches 22 are staggered from the first vapor trenches 12 by an offset distance S, and the second vapor trenches 22 contact the first vapor trenches 12 to form a plurality of staggered vapor passages 102′. By means of the staggered vapor passages 102′, the contact area between the vapor and the passage for transferring heat increases, thereby raising the heat transfer rate to improve the heat transfer efficiency.

Please refer to FIG. 8 showing an embodiment different from FIG. 6. Similarly, the second liquid reverse-flow trenches 23 are staggered from the first liquid reverse-flow trenches 13 by an offset distance S, and the second liquid reverse-flow trenches 23 contact the first liquid reverse-flow trenches 13 to form a plurality of the staggered liquid reverse-flow passages 103′. However, the difference between the present embodiment and FIG. 6 lies in that the second vapor trenches 22 are staggered from the first vapor trenches 12 by an offset distance S and the second vapor trenches 22 contact the first vapor trenches 12 to form a plurality of staggered vapor passages 102′. The staggered liquid reverse-flow passages 103′ and the staggered vapor passages 102′ are disposed to enhance the heat dissipation efficiency.

It is to be understood that the above descriptions are merely preferable embodiment of the example embodiment and not intended to limit the scope of the example embodiment. Equivalent changes and modifications made in the spirit of the example embodiment are regarded as falling within the scope of the example embodiment. 

What is claimed is:
 1. A capillary structure of a slim-type vapor chamber, comprising: an upper board (10), the upper board (10) including a first metal plate (11), a plurality of first trenches (110) being formed on one side surface of the first metal plate (11); and a lower board (20), the lower board (20) including a second metal plate (21), a plurality of second trenches (210) being formed on one side surface of the second metal plate (21), wherein the upper board (10) and the lower board (20) overlap each other to make the two corresponding side surfaces of the first metal plate (11) and the second metal plate (21) contact each other, and the second trenches (210) are staggered from the first trenches (110) by an offset distance (S) to form a plurality of staggered passages (100′).
 2. The capillary structure of the slim-type vapor chamber of claim 1, wherein the first trenches (110) include a plurality of first vapor trenches (12) and a plurality of first liquid reverse-flow trenches (13), the second trenches (210) include a plurality of second vapor trenches (22) and a plurality of second liquid reverse-flow trenches (23), the first vapor trenches (12) and the second vapor trenches (22) are correspondingly disposed to form a plurality of vapor passages (102), and the first liquid reverse-flow trenches (13) and the second liquid reverse-flow trenches (23) are correspondingly disposed to form a plurality of liquid reverse-flow passages (103).
 3. The capillary structure of the slim-type vapor chamber of claim 2, wherein the second vapor trenches (22) are staggered from the first vapor trenches (12) by an offset distance (S) to from a plurality of staggered vapor passages (102′).
 4. The capillary structure of the slim-type vapor chamber of claim 2, wherein the second liquid reverse-flow trenches (23) are staggered from the first liquid reverse-flow trenches (13) to form a plurality of staggered liquid reverse-flow passages (103′).
 5. The capillary structure of the slim-type vapor chamber of claim 2, wherein the first metal plate (11) is further formed with a plurality of first supplementary liquid reverse-flow trenches (14) corresponding to the first liquid reverse-flow trenches (13), the second metal plate (21) is further formed with a plurality of second supplementary liquid reverse-flow trenches (24) corresponding to the second liquid reverse-flow trenches (23), and the first supplementary liquid reverse-flow trenches (14) and the second supplementary liquid reverse-flow trenches (24) are correspondingly disposed to form a plurality of supplementary liquid reverse-flow passages (104).
 6. The capillary structure of the slim-type vapor chamber of claim 2, wherein the first metal plate (11) is formed with a plurality of first liquid transverse reverse-flow trenches (15) perpendicular to the first vapor trenches (12), the second metal plate (21) is formed with a plurality of second liquid transverse reverse-flow trenches perpendicular to the second vapor trenches (22), and the first liquid transverse reverse-flow trenches (15) and the second liquid transverse reverse-flow trenches are correspondingly disposed to form a plurality of liquid transverse reverse-flow passages.
 7. The capillary structure of the slim-type vapor chamber of claim 2, wherein the upper board (10) and the lower board (20) respectively have a thickness below 0.5 mm, the first vapor trenches (12) and the first liquid reverse-flow trenches (13) are formed on the first metal plate (11) by an electroforming method or an etching method, and the second vapor trenches (22) and the second liquid reverse-flow trenches (23) are formed on the second metal plate (21) by an electroforming method or an etching method.
 8. The capillary structure of the slim-type vapor chamber of claim 2, wherein the first liquid reverse-flow trench (13) and the second liquid reverse-flow trench (23) respectively have a width of W, and the offset distance (S) is below ¾W.
 9. The capillary structure of the slim-type vapor chamber of claim 2, wherein a distal end of the first vapor trenches (12) of the first metal plate (11) includes a plurality of first distal-end liquid reverse-flow trenches (16), a distal end of the second vapor trenches (22) of the second metal plate (21) includes a plurality of second distal-end liquid reverse-flow trenches, and the first distal-end liquid reverse-flow trenches (16) and the second distal-end liquid reverse-flow trenches are correspondingly disposed to form a plurality of distal-end liquid reverse-flow passages.
 10. A slim-type vapor chamber, comprising: an upper board (10), the upper board (10) including a first metal plate (11), a plurality of first trenches (110) being formed on one side surface of the first metal plate (11); a lower board (20), the lower board (20) including a second metal plate (21), a plurality of second trenches (210) being formed on one side surface of the second metal plate (21), wherein the upper board (10) and the lower board (20) overlap each other to make two corresponding side surfaces of the first metal plate (11) and the second metal plate (21) contact each other, the second trenches (210) are staggered from the first trenches (110) by an offset distance (S) to form a plurality of staggered passages (100′); and a working fluid filled between the upper board (10) and the lower board (20), the thickness of the slim-type vapor chamber is below 1 mm.
 11. The slim-type vapor chamber of claim 10, wherein the first trenches (110) include a plurality of first vapor trenches (12) and a plurality of first liquid reverse-flow trench (13), the second trenches (210) include a plurality of second vapor trenches (22) and a plurality of second liquid reverse-flow trenches (23), the first vapor trenches (12) and the second vapor trenches (22) are correspondingly disposed to form a plurality of vapor passages (102), and the first liquid reverse-flow trenches (13) and the second liquid reverse-flow trenches (23) are correspondingly disposed to form a plurality of liquid reverse-flow passages (103).
 12. The slim-type vapor chamber of claim 11, wherein the second vapor trenches (22) are staggered from the first vapor trenches (12) by the offset distance (S) to form a plurality of staggered vapor passages (102′).
 13. The slim-type vapor chamber of claim 11, wherein the second liquid reverse-flow trenches (23) are staggered from the first liquid reverse-flow trenches (13) by the offset distance (S) to form a plurality of staggered liquid reverse-flow passages (103′).
 14. The slim-type vapor chamber of claim 11, wherein the first metal plate (11) is formed with a plurality of first supplementary liquid reverse-flow trenches (14) corresponding to the first liquid reverse-flow trenches (13), the second metal plate (21) is formed with a plurality of second supplementary liquid reverse-flow trenches (24) corresponding to the second liquid reverse-flow trenches (23), and the first supplementary liquid reverse-flow trenches (14) and the second supplementary liquid reverse-flow trenches (24) are correspondingly disposed to form a plurality of supplementary liquid reverse-flow passages (104).
 15. The slim-type vapor chamber of claim 11, wherein the first metal plate (11) is formed with a plurality of first liquid transverse reverse-flow trenches (15) perpendicular to the first vapor trenches (12), the second metal plate (21) is formed with a plurality of second liquid transverse reverse-flow trenches perpendicular to the second vapor trenches (22), the first liquid transverse reverse-flow trenches (15) and the second liquid transverse reverse-flow trenches are correspondingly disposed to form a plurality of liquid transverse reverse-flow passages.
 16. The slim-type vapor chamber of claim 11, wherein the upper board (10) and the lower board (20) respectively have a thickness below 0.5 mm, the first vapor trenches (12) and the first liquid reverse-flow trenches (13) are formed on the first metal plate (11) by an electroforming method or an etching method, and the second vapor trenches (22) and the second liquid reverse-flow trenches (23) are formed on the second metal plate (21) by an electroforming method or an etching method.
 17. The slim-type vapor chamber of claim 11, wherein the first liquid reverse-flow trench (13) and the second liquid reverse-flow trench (23) respectively have a width of W, and the offset distance (S) is below ¾W.
 18. The slim-type vapor chamber of claim 11, wherein a distal end of the first vapor trenches (12) of the first metal plate (11) is formed with a plurality of first distal-end liquid reverse-flow trenches (16), a distal end of the second vapor trenches (22) of the second metal plate (21) is formed with a plurality of second distal-end liquid reverse-flow trenches, and the first distal-end liquid reverse-flow trenches (16) and the second distal-end liquid reverse-flow trenches are correspondingly disposed to form a plurality of distal-end liquid reverse-flow passages. 